Natural Fibre
Definition
Fibre of biological or mineral origin. Animal (wool, silk, cashmere, mohair, alpaca), vegetable (cotton, jute, flax, hemp, sisal, coir) or mineral (asbestos; chrysotile remains in regulated use in India, as the 2011 Supreme Court ruling in Kalyaneshwari v. Union of India upheld controlled use and declined to impose a ban).
- Origin categories
- Animal, vegetable, mineral
- Animal examples
- Wool, silk, cashmere, mohair, alpaca
- Vegetable examples
- Cotton, jute, flax, hemp, sisal, coir
- Mineral example
- Asbestos (chrysotile)
Common questions
How does an examiner tell natural fibres apart from synthetic ones under the microscope?+
Natural fibres show irregular, biologically shaped structures, such as the overlapping scale pattern on animal hair or the twisted ribbon form of cotton, while synthetic fibres are extruded and show uniform diameter and cross-section, so morphology is the first sorting criterion before any chemical test.
Is chrysotile asbestos legal to use in India today?+
Its use remains regulated rather than banned. The Supreme Court in Kalyaneshwari v. Union of India (2011) upheld controlled use instead of imposing an outright ban, a position that differs from jurisdictions such as the EU that have banned chrysotile entirely.
Related terms
- Anagen / Catagen / Telogen
- Hair growth phases. Anagen is the active growing phase (about 85 percent of scalp hairs), catagen the brief transition, telogen the resting...
- Cortex
- The middle, and largest, layer of the hair shaft. It contains cortical cells, pigment granules (melanin), and cortical fusi (air spaces). The...
- Cuticle
- The waxy, polymer layer covering the outer surface of leaf epidermal cells. It protects against water loss and herbivory but, forensically, it...
- Follicular Tag
- Translucent sheath tissue adhering to the root of a forcibly pulled hair. Contains nucleated epithelial cells from the inner root sheath and...
- Medulla
- The central canal of the hair shaft, which may be continuous, interrupted, fragmented, or absent. Medullary pattern and the medullary index (medulla...
- Medullary Index
- The ratio of the medulla diameter to the total hair shaft diameter. In companion animal hair identification, a medullary index above 0.5...
- Synthetic Fibre
- Fibre manufactured from regenerated cellulose (rayon, acetate) or polymer chemistry (nylon, polyester, acrylic, polypropylene, spandex, kevlar). Identified by birefringence, FTIR and pyrolysis...